According to known practice, the step of inserting each coil end in the corresponding commutator slot and the preceding step of bending the portion of copper wire adjacent the end of the coil towards the shaft of the rotor, are effected in the intervals between the winding of successive coils, when the winding device for the copper wire is stopped.
This involves a considerable increase in the time necessary for carrying out the overall process. The time necessary to carry out the said operations of insertion and bending during the intervals between the winding of one coil and the winding of the next coil may in fact reach as much as 50% of the total time required for carrying out the whole process.
Attempts have been made in the past to reduce the duration of the pause required between the winding of two successive coils to effect the bending and insertion operations. These attempts have involved use of commutators of a particular type, for example hook commutators, which have not however solved the problem satisfactorily.
The object of the present invention is to avoid the said disadvantage.